From 3e40a1bd90800880b1d3372ffd610df85140b5f0 Mon Sep 17 00:00:00 2001
From: Youssef Gaber <1728215+Gabrola@users.noreply.github.com>
Date: Wed, 10 Sep 2025 02:20:28 +0300
Subject: [PATCH] fix: NATS IPv6 connectivity

---
 lib/sequin/sinks/nats/connection_cache.ex | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/sequin/sinks/nats/connection_cache.ex b/lib/sequin/sinks/nats/connection_cache.ex
index d4f81f3db..93befb0c0 100644
--- a/lib/sequin/sinks/nats/connection_cache.ex
+++ b/lib/sequin/sinks/nats/connection_cache.ex
@@ -158,9 +158,14 @@ defmodule Sequin.Sinks.Nats.ConnectionCache do
       |> put_opt_key(:jwt, sink.jwt)
       |> put_opt_key(:nkey_seed, sink.nkey_seed)
       |> put_tls(sink.tls)
+      |> put_ipv6(sink)
       |> Gnat.start_link()
     end
 
+    defp put_ipv6(opts, %NatsSink{} = sink) do
+      if NatsSink.ipv6?(sink), do: Map.put(opts, :tcp_opts, [:inet6, :binary]), else: opts
+    end
+
     defp put_tls(opts, true) do
       opts
       |> Map.put(:tls, true)